I have always been tremendously attracted — at university I did geography as well as history — to the longue durée French kind of history, which has a risk of determinism in it but, done well, a sense that time and space are part of the matrix within which human beings existed and exist is tremendously important. To give people a sense of place as well as time, I think that's very significant. 

DJ: Norman, as a case history, a very big one, let's look at the Cold War. Could it have gone differently? Could it have ended differently? When you came on to the scene in the '70s and '80s, do you think it made a big difference the way that people like Mrs Thatcher, Ronald Reagan, the Pope behaved? Did the decisions they took matter? Could the whole story have ended quite differently?

NS: Yes, I think not there and then, in the sense that it would have taken quite a long time to dismantle the West in any sense. But if you think of the world of the latter 1970s — 25 per cent inflation in the heartland, this country farcically unworkable, the West Germans running to Moscow, even Franz Josef Strauss trying to make terms with them over recognising that absurd little statelet East Germany, Frenchmen turning up in Hungary and saying, "Oh, this is just like Sweden" — it was a crazy world. 

It is certainly thinkable that if that had been allowed to go on, if it hadn't been for a Reagan/Thatcher reaction in 1979-80, that things could indeed have been ugly. We had that splendid fightback period in the first half of the '80s. It goes back in the end to Henry Kissinger in 1975, and the idea that you can actually draw up rules for the economy of the West which will drive out inflation even at the cost of some short-term pain. That took some courage to do, it certainly did. What would have happened to this country? 

Since we're in London, what would have happened? There was nobody else in the Tory party except Margaret Thatcher who had that combination of gifts, and even then her candidacy came up completely accidentally. Keith Joseph, who was proposing to stand, had allowed Alfred Sherman to write his speeches, and they were such spiffingly good speeches that he gave up reading them carefully before he read them out. So Joseph went to speak in Birmingham in 1974. 

He then discovered that Alfred Sherman had written a speech saying — sounding not unlike some German eugenicist — that the trouble was that the proletariat, especially "those of low intelligence", were having too many children.  So the choice was to give them contraception or face national "degeneration". So Keith Joseph was then immortally pilloried in Private Eye as "Sir Sheath". They met that evening in Flood Street, where Mrs T was cooking — fried eggs or something in the kitchen — and Keith Joseph said with his head in his hands, "Well, I can't possibly stand after this" as the wolves bayed outside. She came in dancing in with her frying pan and said, "Well, if you're not going to stand, I will." In some ways, it's very tempting to look at it like that. 

DJ: I'm not trying to trivialise history. It's not just about individual quirks and character. But I do think the story of the Cold War is simply one of many examples of a major historical event where individuals, and also individual nations, played a key role.